1. Technical Field
The present disclosure relates to valve system adapted to permit the introduction of surgical instrumentation into a patient's body. More particularly, the present disclosure relates to a low profile valve system for use with an introducer which is intended for insertion into a patient's body and to receive an instrument in sealing engagement therewith.
2. Description of the Related Art
The term “laparoscopy” typically includes a variety of surgical procedures involving one or more remotely operated surgical instruments which are inserted through the interior of the abdomen through one or more surgical incisions to access the operating cavity. “Endoscopic” procedures involve accessing hollow viscera of the body through one or more narrow tubes or cannula inserted through a small entrance incision in the skin. Laparoscopic and endoscopic procedures generally require that any instrumentation inserted into the body be sealed to limit the possibility of infection and to maintain the operating cavity insufflated (if needed). Moreover, laparoscopic and endoscopic procedures often require the surgeon to act on organs, tissue, and vessels far removed from the incision, thereby requiring that any instruments used in such procedures be relatively long and narrow.
For such procedures, the introduction of a tube into certain anatomical cavities such as the abdominal cavity is usually accomplished by use of a trocar assembly made up of a cannula assembly and an obturator assembly. Since the cannula assembly provides a direct passage for surgical instrumentation from outside the patient's body to access internal organs and tissue, it is important that the cannula assembly maintain a relatively gas-tight interface between the abdominal cavity and the outside atmosphere. The cannula assembly generally includes a cannula attached to a cannula housing containing a seal assembly adapted to maintain a seal across the opening of the cannula housing.
Since surgical procedures in the abdominal cavity of the body require insufflating gases to raise the cavity wall away from vital organs, the procedure is usually initiated by use of a so-called Verres needle through which a gas such as CO2 is introduced into the body cavity, thereby creating a pneumoperitoneum. The gas provides a positive pressure which raises the inner body wall away from internal organs, thereby providing the surgeon with a region within which to operate thereby avoiding unnecessary contact with the organs during surgery. An obturator or trocar is inserted into the cannula assembly and used to puncture the abdominal wall. Following removal of the obturator or trocar from the cannula assembly, laparoscopic or endoscopic surgical instruments may be inserted through the cannula assembly to perform surgery within the abdominal cavity. Without the obturator assembly to block the flow of insufflation gas out from the cavity, other structure must be provided to maintain a relatively fluid-tight interface between the abdominal cavity and the outside atmosphere.
Generally in the context of insufflatory surgical procedures a substantially fluid-tight seal is necessary at all times, e.g., during instrument insertion, during instrument manipulation, during instrument immobility (i.e., when an instrument is idle or not being manipulated by the surgeon or technician) and when an instrument is not present in the cannula. In certain cases, the height of the valve system relative to the patient skin may cause interference with the surgeon's ability to manipulate the instrument within the operating cavity which may in some cases cause a disruption or interference with the fluid-tight seal resulting in relative deflation of the pneumoperitoneum (in the minor instance) to contamination of the operating cavity (in a critical instance).
As a result, attempts have been made to improve the overall seal in conjunction with a cannula assembly to maintain the integrity of the seal between the body cavity and the atmosphere outside the patient's body. However, such systems to date have failed to address the full range of surgeons' needs against the potential risks they propose when manipulating instruments within tight operating cavities. A need also exists for surgical devices and methods which anchor a cannula and instrument support housings (or other access member) to a patient with minimum tissue trauma while still providing a positive seal.